Electrically-welded girder



Y 1,638,636 Allg9 1927 s. LACHMAN ELEGTRI CALLY WELDED GIRDER OriginalFiled Nov. 9, 1923 f. MA.

gwenbofc Lau/'ence Lockman Patented Aug; 9, 1927.

`UNI''ED STATES l ree-aen PATENT carica.

LAURENCE S. LACHMAN, 0F NEW YORK, N. Y., ASSIGN'OR T0 UNIVERSAL ELEGTRICyTTIElIiIDIN'G COMPANY, A CORPORATION OF vNEW YORKe ELECTRICALLY-WELDEDGIRDER.

.application led November 9, 1923, Serial No. 673,658.y Renewed Hay 5,1927. l

vide great strength or ability to withstand' both vertical and lateralstresses andin a `way to secure cheapness of construction and facilityfor application of the electrical resistance and pressure method ofwelding the parts together. v Y

Y My invention consists ofa girder or the like constructed ashereinafter described and shown in the accompanying drawings and thenmore, particularly specified in thev claims. Y

'In carrying out my present invention I prefer to -utilize features ofconstruction described in my accompanying application, ser. No. 673,657sled November e, 1923y wherein I -have set forth a structure in whichvthe diagonal consists of a plate disposed with its plane transverse tothe general plane of the girder and welded by the outside face vof thebend in said plate to the outer angle or corner ofthe angle bar. y

My invention, however, might be carried out by using other forms 0f lon'tudinal members suited for the welding of t e angles of a zig-za baradapted to form diagonals by the ben s of the zig-zag.

In the accompanying drawings:

' Fi l is a side elevation of a girder or the li e embodying myinvention.

\ Fig. 2 is a section on the line 2-2.

Fig. 3 is a plan of Fig. 1.

Thetwoy longitudine s or the upper and lower members of theV structureshown at 1 consist preferabl of angle bars disposed in the same generaplane and with t e outer angles proiected toward one another. To each ofsaid longitudinale is welded a zig-zag bar 2 said zig-zag bar consistingreferably of aiat bar with its edge presented, laterally,

x buttons 4 applic or in other words with the plane of the bar arrangedtransverse to the general plane of the structure. By preference likewiseeach of said bars is provided with a pair of indented ribs 3 betweenwhich and to the upper face of the bend forming the zig-zag, the upperangle or corner of the bar 1 is welded as 'described in my companionapplication by the use of the electrical resistance and pres` suremethod. By the Aexpression indented r1bs,7 I mean the ordinary struck upribs whereby on one side of the bar there are the projecting elements 3and onthe other side there are depressions or Vgrooves 3. Alternatingbends of each zig-zag 2 are thus welded to the horizontals by the outerface of the bend while the intermediate bends of the two barsrespectively meet so that when they are welded to one another a girderor the like of the lattice type will be formed or in other words onewherein-the diagonale cross one another. The intermediate tbends thuspresented to one another may be welded electrically directly to oneanother, the curve of the bends 4aiding the process because of the smallarea of contact afforded for passage of the current and development ofheat. The heating effect is enhanced furthermore, by reason of the factthat, where the bends engageeach other Wherethe area is restricted dueto the indentations.' The strength of the union at. the crossing pointsof the diagonals may be further increased by electrically welding themto ether by the use of rigid to o pcsite edges of the plates 2 andwelded t creto by the application of electric heating current 4andpressure as well understood in the art. These buttons firmly secure thetwo zig-zags together at the crossings of the lattice and further areuseful in takin care of any failure' of the bends to exactfy align withone another when the parts are assembled in the welding machine. j

What I claimas my invention is:

1. A structural beam com risin parallel angle members, the apices t ereoopposed grooved surfaces.

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2. A structural beam com risin parallel angle members, the api'ces tereo opposed to each other, vtwo zigzag members, the planes of which aretransverse to the general plane of 4the beam, each provided withparallel indented ribs, and each electrically Welded at its outer bendsto the apex of an angle bar, so that the sides of the angle seat uponthe ribs and the inner bends thereof being electrically welded to eachother at their rooved surfaces.

3. structural beam comprising parallel angle members, the apices thereofopposed to each other, two zigzag members each provided with parallelindented ribs, each of the zigzag members electrically welded at itsouter bends to the apex of an angle member, so that the sides of theangle seat upon the ribs, and the inner bends of the angle members beingelectrically Welded at their LAURENCE s. LACHMAN.

